Default VLAN on Most Switches | Generated by AI
Question: Which VLAN is the default VLAN on most switches?
Answer:
The correct answer is B) VLAN 1.
On most network switches (particularly Cisco switches and many other vendors that follow similar conventions), VLAN 1 is configured as the default VLAN. This means:
- All switch ports are initially assigned to VLAN 1 unless explicitly changed.
- VLAN 1 is often used for management traffic (e.g., Telnet, SSH, SNMP, or CDP/LLDP).
- It is also the default native VLAN on trunk ports, meaning untagged frames are associated with VLAN 1.
- Best practices recommend changing the native VLAN and avoiding the use of VLAN 1 for regular data traffic due to security concerns (e.g., potential VLAN hopping attacks).
Other options:
- VLAN 0: Typically reserved or not usable (often for internal purposes like blackholing traffic).
- VLAN 100: Not a default; part of extended VLAN range, user-configurable.
- VLAN 1001: Usually in the reserved range (1002–1005 are defaults for legacy token ring/FDDI on Cisco), and 1001 is not used as default.
This is standard across most enterprise switches from Cisco, Arista, Juniper (with some variations), and others.